[go: up one dir, main page]

WO2011061591A1 - Improved process for the preparation of 1-benzyl-4-(5,6-dimethoxy-1-indanone)-2-yl)methyl piperidine hydrochloride form-iii - Google Patents

Improved process for the preparation of 1-benzyl-4-(5,6-dimethoxy-1-indanone)-2-yl)methyl piperidine hydrochloride form-iii Download PDF

Info

Publication number
WO2011061591A1
WO2011061591A1 PCT/IB2010/002916 IB2010002916W WO2011061591A1 WO 2011061591 A1 WO2011061591 A1 WO 2011061591A1 IB 2010002916 W IB2010002916 W IB 2010002916W WO 2011061591 A1 WO2011061591 A1 WO 2011061591A1
Authority
WO
WIPO (PCT)
Prior art keywords
donepezil hydrochloride
form iii
preparation
indanone
dimethoxy
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/IB2010/002916
Other languages
French (fr)
Inventor
Anil Ganpatrao Holkar
Dharam Vir
Manoj Mukhopadhyay
Ravindra Bhat
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Jubilant Pharmova Ltd
Original Assignee
Jubilant Life Sciences Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jubilant Life Sciences Ltd filed Critical Jubilant Life Sciences Ltd
Publication of WO2011061591A1 publication Critical patent/WO2011061591A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D211/00Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings
    • C07D211/04Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings with only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D211/06Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having no double bonds between ring members or between ring members and non-ring members
    • C07D211/08Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having no double bonds between ring members or between ring members and non-ring members with hydrocarbon or substituted hydrocarbon radicals directly attached to ring carbon atoms
    • C07D211/18Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having no double bonds between ring members or between ring members and non-ring members with hydrocarbon or substituted hydrocarbon radicals directly attached to ring carbon atoms with substituted hydrocarbon radicals attached to ring carbon atoms
    • C07D211/30Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having no double bonds between ring members or between ring members and non-ring members with hydrocarbon or substituted hydrocarbon radicals directly attached to ring carbon atoms with substituted hydrocarbon radicals attached to ring carbon atoms with hydrocarbon radicals, substituted by doubly bound oxygen or sulfur atoms or by two oxygen or sulfur atoms singly bound to the same carbon atom
    • C07D211/32Heterocyclic compounds containing hydrogenated pyridine rings, not condensed with other rings with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having no double bonds between ring members or between ring members and non-ring members with hydrocarbon or substituted hydrocarbon radicals directly attached to ring carbon atoms with substituted hydrocarbon radicals attached to ring carbon atoms with hydrocarbon radicals, substituted by doubly bound oxygen or sulfur atoms or by two oxygen or sulfur atoms singly bound to the same carbon atom by oxygen atoms

Definitions

  • the present invention in general relates to improved process for preparing polymorphic form of l-benzyl-4-(5,6-dimethoxy-l-indanone)-2-yl)methyl piperidine hydrochloride (Donepezil hydrochloride). More particularly, the present invention provides an improved process for the preparation of Donepezil hydrochloride Form III in high yield and high purity.
  • Donepezil Hydrochloride of formula I is first disclosed in US 4,895,841 is known for its excellent anti-acetyl-cholinesterase activity and it is an effective active ingredient in pharmaceutical preparations for treatment and prevention of diseases such as Alzheimer disease and senile dementia.
  • US20050215591 disclosed Donepezil hydrochloride form HI and H2 along with Donepezil hydrochloride as monohydrate and sesquihydrate.
  • US6,140,321 and US5,985,864 describes process for preparation of form III by recrystallizing Donepezil hydrochloride form I or by dissolving Donepezil hydrochloride form II in suitable solvent and precipitating the desired form by addition of an anti-solvent.
  • Donepezil free base is dissolved in suitable solvent and treated with hydrochloric acid or hydrogen chloride or by humidification of any form to give desired form III, wherein all the processes disclosed contained use of large volumes of solvents, which is not only difficult to handle on the commercial scale but also pose environment hazards.
  • US7,479,563 discloses a process for preparation of form III by dissolving Donepezil in ethanol and adding hydrochloric acid to get the desired form, the given process suffers a drawback of very long reaction time, which leads to the formation of impurities leading to decrease in purity levels.
  • WO2009084030 discloses a process for preparation of Donepezil hydrochloride form III using methanol/acetone, but the process is not compatible at industrial scale as it too uses large volumes of solvents, which is an environment and economical hazard.
  • an improved process for preparation of l-benzyl-4-(5,6-dimethoxy-l-indanone)-2- yl)methyl piperidine hydrochloride (Donepezil hydrochloride) form III comprising dissolving Donepezil hydrochloride in an halogenated solvent to prepare a solution, removing the solvent to obtain solid residue, adding alcoholic solvent to precipitate Donepezil hydrochloride form III and isolating the precipitated Donepezil hydrochloride form III.
  • Donepezil hydrochloride as used in step (a) can be prepared from any of the processes described in prior art.
  • Halogenated solvent used in step (a) is selected from the group comprising of dichloromethane, dichloroethane, chloroform and the like.
  • Step (a) Reaction of step (a) is carried out at temperature range of 20-50°C and preferably 30-40°C.
  • Alcoholic solvent used in step (c) can be selected from C1-C4 alcohol.
  • the said alcohol is selected from the group comprising of methanol, ethanol, n-propanol, iso-propanol, n-butanol, isobutanol and the like or mixture thereof.
  • Isolation of Donepezil hydrochloride form III in step (d) is performed by any conventional method like filtration.
  • donepezil hydrochloride form III obtained by the process described herein possess the relative particle size distribution as having D(0.1) not more than 10 ⁇ ⁇ and D(0.9) not more than 500 ⁇ .
  • the present invention also provides the median particle size D(0.5) of donepezil hydrochloride form III of not more than 200 ⁇ .
  • D(0.9) as used herein is defined as a size of particles where 90 volume percent of the particles have sizes less than the value given.
  • D(0.5) defines a size where 50 volume percent of the particles have sizes less than the specified value.
  • D(0.1) defines a size where 10 volume percent of the particles have sizes less than the specified value.
  • Donepezil hydrochloride (25 g) was taken in dichloromethane (125 ml) at 25-

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Hydrogenated Pyridines (AREA)

Abstract

Disclosed herein an improved process for the preparation of polymorphic form III of Donepezil hydrochloride.

Description

IMPROVED PROCESS FOR THE PREPARATION OF l-BENZYL-4-(5,6- DIMETHOXY-l-INDANONE)-2-YL)METHYL PIPERIDINE
HYDROCHLORIDE FORM-III
FIELD OF INVENTION
The present invention in general relates to improved process for preparing polymorphic form of l-benzyl-4-(5,6-dimethoxy-l-indanone)-2-yl)methyl piperidine hydrochloride (Donepezil hydrochloride). More particularly, the present invention provides an improved process for the preparation of Donepezil hydrochloride Form III in high yield and high purity.
BACKGROUND OF THE INVENTION
Donepezil Hydrochloride of formula I is first disclosed in US 4,895,841 is known for its excellent anti-acetyl-cholinesterase activity and it is an effective active ingredient in pharmaceutical preparations for treatment and prevention of diseases such as Alzheimer disease and senile dementia.
Figure imgf000002_0001
As Donepezil hydrochloride is administered orally, thus its stability against heat and humidity during storage was an important concern, thus a stable form was always desirable, subsequently, US 5,985,864 disclosed five crystalline forms of Donepezil hydrochloride, i.e. I, II, III, IV and V as a result of extensive research to achieve stable form of Donepezil hydrochloride.
US7, 186,842 disclosed novel polymorphic form of Donepezil hydrochloride as form VI.
US20050215591 disclosed Donepezil hydrochloride form HI and H2 along with Donepezil hydrochloride as monohydrate and sesquihydrate.
Recently, US2009137811 disclosed Donepezil hydrochloride as hemihydrate and dihydrate. Each of the disclosed forms have distinct intrinsic powder X-ray diffraction pattern, infra-red spectrum and other properties, but of all the forms, form III of Donepezil hydrochloride has more marked characteristics than other crystal types; specifically it has low hygroscopicity and higher heat stability. Keeping this in view many processes has been developed for the preparation of form III.
US6,140,321 and US5,985,864 describes process for preparation of form III by recrystallizing Donepezil hydrochloride form I or by dissolving Donepezil hydrochloride form II in suitable solvent and precipitating the desired form by addition of an anti-solvent. Alternatively Donepezil free base is dissolved in suitable solvent and treated with hydrochloric acid or hydrogen chloride or by humidification of any form to give desired form III, wherein all the processes disclosed contained use of large volumes of solvents, which is not only difficult to handle on the commercial scale but also pose environment hazards.
US7,479,563 discloses a process for preparation of form III by dissolving Donepezil in ethanol and adding hydrochloric acid to get the desired form, the given process suffers a drawback of very long reaction time, which leads to the formation of impurities leading to decrease in purity levels.
WO2009084030 discloses a process for preparation of Donepezil hydrochloride form III using methanol/acetone, but the process is not compatible at industrial scale as it too uses large volumes of solvents, which is an environment and economical hazard.
Thus, from the preceding literature it is apparent that the processes suffer incompatibilities in terms of being applicable at industrial level.
Thus, there is a continuing <need for the development of eco-friendly and cost effective process for the preparation of Donepezil hydrochloride form III that is devoid of the limitation of the processes known in the prior art.
OBJECT AND SUMMARY OF THE INVENTION
It is an object of the present invention to improve upon limitations in the prior art by providing a commercially viable and environment friendly process for producing Donepezil hydrochloride form III in high yield and high purity.
In accordance with one preferred embodiment of the present invention, there is provided a process for the preparation of polymorphic form III of l-benzyl-4-(5,6- dimethoxy-l-indanone)-2-yl)methyl piperidine hydrochloride (Donepezil hydrochloride) comprising the steps of:
a) mixing Donepezil hydrochloride and halogenated solvent;
b) removing the halogenated solvent;
c) adding alcoholic solvent and
d) isolating the polymorphic form III of Donepezil hydrochloride.
DETAILED DESCRIPTION OF THE INVENTION
While this specification concludes with claims particularly pointing out and distinctly claiming that, which is regarded as the invention, it is anticipated that the invention can be more readily understood through reading the following detailed description of the invention and study of the included examples.
According to one embodiment of the present invention, there is provided an improved process for preparation of l-benzyl-4-(5,6-dimethoxy-l-indanone)-2- yl)methyl piperidine hydrochloride (Donepezil hydrochloride) form III, comprising dissolving Donepezil hydrochloride in an halogenated solvent to prepare a solution, removing the solvent to obtain solid residue, adding alcoholic solvent to precipitate Donepezil hydrochloride form III and isolating the precipitated Donepezil hydrochloride form III.
In accordance with one preferred embodiment of the present invention, there is provided a process for the preparation of polymorphic form III of l-benzyl-4-(5,6- dimethoxy- 1 -indanone)-2-yl)methyl piperidine hydrochloride (Donepezil hydrochloride) comprising the steps of:
a) mixing Donepezil hydrochloride and halogenated solvent;
b) removing the halogenated solvent;
c) adding alcoholic solvent and
d) isolating the polymorphic form III of Donepezil hydrochloride.
Donepezil hydrochloride, as used in step (a) can be prepared from any of the processes described in prior art.
Halogenated solvent used in step (a) is selected from the group comprising of dichloromethane, dichloroethane, chloroform and the like.
Reaction of step (a) is carried out at temperature range of 20-50°C and preferably 30-40°C. Alcoholic solvent used in step (c) can be selected from C1-C4 alcohol. The said alcohol is selected from the group comprising of methanol, ethanol, n-propanol, iso-propanol, n-butanol, isobutanol and the like or mixture thereof.
Isolation of Donepezil hydrochloride form III in step (d) is performed by any conventional method like filtration.
According to a further embodiment of the present invention, donepezil hydrochloride form III obtained by the process described herein possess the relative particle size distribution as having D(0.1) not more than 10 μιη and D(0.9) not more than 500 μηι. The present invention also provides the median particle size D(0.5) of donepezil hydrochloride form III of not more than 200 μηι.
The term "particle size distribution" as used herein refers to the relative percentages by weight or volume of each of the different size fractions of a particulate matter. The term "median particle; size" as used herein refers to the median or 50% quantile of a particle size distribution.
The term D(0.9) as used herein is defined as a size of particles where 90 volume percent of the particles have sizes less than the value given. The term D(0.5) defines a size where 50 volume percent of the particles have sizes less than the specified value. The term D(0.1) defines a size where 10 volume percent of the particles have sizes less than the specified value.
The process for the preparation of form III of Donepezil hydrochloride described in the present invention is demonstrated in the examples illustrated below. These examples are provided as illustration only and therefore should not be construed as limitation of the scope of the invention.
Example 1
Preparation of Donepezil Hydrochloride Polymorphic Crystalline Form III
Donepezil hydrochloride (80 g) was taken in dichloromethane (400 ml) at 25- 30 °C. The resulting solution was heated to 35-40°C. The dichloromethane was distilled off completely under vacuum below 40°C and the resulting residue was kept under vacuum for 30 minutes. To the resulting residue, isopropanol (560 ml) was added and heated to reflux, under stirring for 1 hour at reflux temperature. The resulting reaction mass was cooled to 20-25 °C and stirred for 1 hour. The resulting solid was filtered, suck dried, washed with isopropanol (240 ml) and finally dried under vacuum at 50-55°C to afford 64 g of the title compound. HPLC purity 99.9%. The relative particle size distribution is having D(0.1) = 5.127 μηι, D(0.5) = 58.714 μηι and D(0.9) = 253.628 μιη.
Example 2
Preparation of Donepezil Hydrochloride Polymorphic Crystalline Form III
Donepezil hydrochloride (50 g) was taken in dichloromethane. (250 ml) at 25-
30 °C. The resulting solution was heated to 35-40°C. The dichloromethane was distilled off completely under vacuum below 40°C and the resulting residue was kept under vacuum for 30 minutes. To the resulting residue, methanol (350 ml) was added and heated to reflux, under stirring for 1 hour at reflux temperature. The resulting reaction mass was cooled to 20-25 °C and stirred for 1 hour. Distilled 175 ml of methanol under vacuum at 43°C, and cooled to 20-25 °C. Seeded with 0.5 g of Donepezil hydrochloride Form III. Stirred for 2 h at 20-25°C, and solid comes out. The resulting solid was filtered, suck dried, washed with methanol (25 ml) and finally dried under vacuum at 50-55°C to afford 31 g of the title compound.
Example 3
Preparation of Donepezil Hydrochloride Polymorphic Crystalline Form III
Donepezil hydrochloride (40 g) was taken in chloroform (200 ml) at 25-30 °C. The resulting solution was heated to 35-40°C. The chloroform was distilled off completely under vacuum below 40°C and the resulting residue was kept under vacuum for 30 minutes. To the resulting residue, isopropanol (280 ml) was added and heated to reflux, under stirring for 1 hour at reflux temperature. The resulting reaction mass was cooled to 20-25 °C and stirred for 1 hour. The resulting solid was filtered, suck dried, washed with isopropanol (120 ml) and finally dried under vacuum at 50- 55°C to afford 31.5 g of the title compound.
Example 4
Preparation of Donepezil Hydrochloride Polymorphic Crystalline Form III
Donepezil hydrochloride (40 g) was taken in dichloroethane (200 ml) at 25-30 °C. The resulting mixture was heated to 50° C. The dichloroethane was distilled off completely under vacuum below 50°C and the resulting residue was kept under vacuum for 30 minutes. To the resulting residue, isopropanol (280 ml) was added and heated to reflux, under stirring for 1 hour at reflux temperature. The resulting reaction mass was cooled to 20-25 °C and stirred for 1 hour. The resulting solid was filtered, suck dried, washed with isopropanol (120 ml) and finally dried under vacuum at 50- 55 °C to afford 32 g of the title compound.
Example 5
Preparation of Donepezil Hydrochloride Polymorphic Crystalline Form III
Donepezil hydrochloride (25 g) was taken in dichloromethane (125 ml) at 25-
30 °C. The resulting mixture was heated to 35-40°C. The dichloromethane was distilled off completely under vacuum below 40° C and the resulting residue was kept under vacuum for 30 minutes. To the resulting residue, n-butanol (100 ml) was added and heated to reflux, under stirring for 1 hour at reflux temperature. The resulting reaction mass was cooled to 20-25 °C and stirred for 1 hour. The resulting solid was filtered, suck dried, washed with n-butanol (25 ml) and finally dried under vacuum at 50-55°C to afford 22 g of the title compound.
While this invention has been described in detail with reference to certain preferred embodiments, it should be appreciated that the present invention is not limited to those precise embodiments. Rather, in view of the present disclosure, which describes the current best mode for practicing the invention, many modifications and variations would present themselves to those skilled in the art without departing from the scope and spirit of this invention.

Claims

We claim:
1. A process for the preparation of polymorphic form III of l-benzyl-4-(5,6- dimethoxy-l-indanone)-2-yl)methyl piperidine hydrochloride (Donepezil hydrochloride) comprising the steps of:
a) mixing Donepezil hydrochloride and halogenated solvent;
b) removing the halogenated solvent;
c) adding alcoholic solvent and
d) isolating the polymorphic form III of Donepezil hydrochloride.
2. The process according to claim 1, wherein the halogenated solvent used in step (a) is selected from the group comprising of dichloromethane, dichloroethane and chloroform.
3. The process according to claim 2, wherein the preferred halogenated solvent is dichloromethane.
4. The process according to claim 1, wherein the alcoholic solvent used in step (c) is selected from Ci-C4 alcohol.
5. The process according to claim 4, wherein the alcoholic solvent used is selected from the group comprising of methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, t-butanol or mixture thereof.
6. The process according to claim* 5, wherein the preferred alcoholic solvent is iso- propanol.
7. The process according to claim 1, wherein reaction temperature in step (a) is 20- 50°C and preferably 30-40°C.
8. The particle size of polymorphic form III of l-benzyl-4-(5,6-dimethoxy-l- indanone)-2-yl)methyl piperidine hydrochloride (Donepezil hydrochloride) according to claim 1 is having D(0.1) not more than 10 μιη, D(0.5) not more than 200 μιη and D(0.9) not more than 500 μηι.
9. A process for the preparation of polymorphic form III of l-benzyl-4-(5,6- dimethoxy- 1 -indanone)-2-yl)methyl piperidine hydrochloride (Donepezil hydrochloride) comprising the steps of:
a) mixing Donepezil hydrochloride and dichloromethane;
b) removing the dichloromethane;
c) adding iso-propanol and 1
d) isolating the polymorphic form III of Donepezil hydrochloride.
PCT/IB2010/002916 2009-11-18 2010-11-16 Improved process for the preparation of 1-benzyl-4-(5,6-dimethoxy-1-indanone)-2-yl)methyl piperidine hydrochloride form-iii Ceased WO2011061591A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN2379/DEL/2009 2009-11-18
IN2379DE2009 2009-11-18

Publications (1)

Publication Number Publication Date
WO2011061591A1 true WO2011061591A1 (en) 2011-05-26

Family

ID=43568163

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2010/002916 Ceased WO2011061591A1 (en) 2009-11-18 2010-11-16 Improved process for the preparation of 1-benzyl-4-(5,6-dimethoxy-1-indanone)-2-yl)methyl piperidine hydrochloride form-iii

Country Status (1)

Country Link
WO (1) WO2011061591A1 (en)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4895841A (en) 1987-06-22 1990-01-23 Eisai Co., Ltd. Cyclic amine compounds with activity against acetylcholinesterase
US5985864A (en) 1996-06-07 1999-11-16 Eisai Co., Ltd. Polymorphs of donepezil hydrochloride and process for production
US6140321A (en) 1996-06-07 2000-10-31 Eisai Co., Ltd. Polymorphs of donepezil hydrochloride and process for production
EP1323712A1 (en) * 2000-09-25 2003-07-02 Eisai Co., Ltd. Process for producing multiform crystal of donepezil hydrochloride
WO2004092137A1 (en) * 2003-04-16 2004-10-28 Hetero Drugs Limited Novel crystalline forms of donepezil hydrochloride
WO2006111983A2 (en) * 2005-04-21 2006-10-26 Jubilant Organosys Limited NOVEL POLYMORPHIC FORM OF (l-BENZYL-4-[(5,6-DIMETHOXY-l- INDANONE)-2-YL]METHYL PIPERIDINE HYDROCHLORIDE AND PROCESS FOR PREPARING THE SAME
US7186842B2 (en) 2003-02-12 2007-03-06 Usv, Ltd. Polymorph of (1-benzyl-4-[(5,6-dimethoxy-1-indanone)-2-y1] methyl piperidine hydrochloride (Donepezil hydrochloride) and a process for producing thereof
US20090137811A1 (en) 2005-07-30 2009-05-28 Pliva Hrvatska D.O.O Process for the preparation of donepezil and intermediate compounds thereof as well as hydrates of donepezil
WO2009084030A2 (en) 2007-12-03 2009-07-09 Neuland Laboratories Ltd. Improved process for the preparation of (1-benzyl-4-(5,6,- dimethoxyind anone-2-yl)methylpiperidine) hydrochloride-form iii

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4895841A (en) 1987-06-22 1990-01-23 Eisai Co., Ltd. Cyclic amine compounds with activity against acetylcholinesterase
US5985864A (en) 1996-06-07 1999-11-16 Eisai Co., Ltd. Polymorphs of donepezil hydrochloride and process for production
US6140321A (en) 1996-06-07 2000-10-31 Eisai Co., Ltd. Polymorphs of donepezil hydrochloride and process for production
EP1323712A1 (en) * 2000-09-25 2003-07-02 Eisai Co., Ltd. Process for producing multiform crystal of donepezil hydrochloride
US7479563B2 (en) 2000-09-25 2009-01-20 Eisai R&D Management Co., Ltd. Method of producing polymorphic crystals of donepezil hydrochloride
US7186842B2 (en) 2003-02-12 2007-03-06 Usv, Ltd. Polymorph of (1-benzyl-4-[(5,6-dimethoxy-1-indanone)-2-y1] methyl piperidine hydrochloride (Donepezil hydrochloride) and a process for producing thereof
WO2004092137A1 (en) * 2003-04-16 2004-10-28 Hetero Drugs Limited Novel crystalline forms of donepezil hydrochloride
US20050215591A1 (en) 2003-04-16 2005-09-29 Hetero Drugs Limited Novel crystalline forms of donepezil hydrochloride
WO2006111983A2 (en) * 2005-04-21 2006-10-26 Jubilant Organosys Limited NOVEL POLYMORPHIC FORM OF (l-BENZYL-4-[(5,6-DIMETHOXY-l- INDANONE)-2-YL]METHYL PIPERIDINE HYDROCHLORIDE AND PROCESS FOR PREPARING THE SAME
US20090137811A1 (en) 2005-07-30 2009-05-28 Pliva Hrvatska D.O.O Process for the preparation of donepezil and intermediate compounds thereof as well as hydrates of donepezil
WO2009084030A2 (en) 2007-12-03 2009-07-09 Neuland Laboratories Ltd. Improved process for the preparation of (1-benzyl-4-(5,6,- dimethoxyind anone-2-yl)methylpiperidine) hydrochloride-form iii

Similar Documents

Publication Publication Date Title
US8664222B2 (en) Specific salt, anhydrous and crystalline form of a dihydropteridione derivative
US8329695B2 (en) Crystalline form of the free base N-[trans-4-[4-(cyclopropylmethyl)-1-piperazinyl]cyclohexyl]-4-[[(7r)-7-ethyl-5,6,7,8-tetrahydro-5-methyl-8-(1-methylethyl)-6-oxo-2-pteridinyl]amino]-3-methoxy-benzamide
CN101679218B (en) Crystalline minocycline base and processes for its preparation
CN101006090A (en) Hydrates and polymorphs of 4-[[(7r)-8-cyclopentyl-7-ethyl-5,6,7,8-tetrahydro-5-methyl-4-6-oxo-2-piperidinyl]amino]-3-methoxy-n-(1-methyl-4-piperidinyl)-benzamide, methods for the production thereof
EP2760853A1 (en) Novel salts of alogliptin
US9624207B2 (en) Polymorphs of azilsartan medoxomil
US20080091023A1 (en) Processes for optical resolution of 1-phenyl-1,2,3,4-tetrahydroisoquinoline
US11161871B2 (en) Crystalline form of obeticholic acid and preparation method therefor
AU2012264476B2 (en) Process for the preparation of paliperidone
EP2658840B1 (en) Process for making fingolimod hydrochloride crystals
US20210300917A1 (en) Solid State Forms of an Apoptosis-Inducing Agent and Processes Thereof
US20140112992A1 (en) Process for febuxostat
WO2011061591A1 (en) Improved process for the preparation of 1-benzyl-4-(5,6-dimethoxy-1-indanone)-2-yl)methyl piperidine hydrochloride form-iii
WO2014195977A2 (en) Novel polymorphs of vismodegib
CA2808731A1 (en) Crystalline forms of maraviroc phosphate and process for maraviroc amorphous form
CA2811912A1 (en) Novel polymorphs of febuxostat
US11161853B2 (en) Method for isolation and purification of naltrexone
US20060258705A1 (en) Process for making crystalline donepezil hydrochloride monohydrate
US20060264637A1 (en) Preparation of paroxetine hydrochloride hemihydrate

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 10805293

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 10805293

Country of ref document: EP

Kind code of ref document: A1